It’s a gorgeous day here in glassland, rained just enough yesterday to turn the car into a mud-spattered mess, and I stopped off at the carwash on the way home. Only about 500 people had the same idea, and while I waited patiently in line I spotted two teenage girls poking fun at a dumpy middle-aged lady.

She was chubby, no make-up, torn sweats and an old t-shirt, hair was a mess. She obviously ran out for a few things and didn’t think it was worth fixing herself up just to go to the store and then sit on a park bench waiting for the bus. Since I’d done just about the same for my errands this morning, she had my deepest sympathy.

It was just too bad that she was sitting at a bus stop with two teens tricked out in full warpaint. They were sneering, sotto voce: “Oh my god, she’s buying donuts? That’s the last thing she needs. Look at her. I wouldn’t leave the house looking like that. S***, I wouldn’t leave the bathroom looking like that.”

Now obviously, if I could hear them 10 feet away in my car, this lady could, too, but she gave no sign. She picked up a folded newspaper that someone had left on the bench, and sat stolidly reading while I inched up in the carwash line and the girls went on and on.

Of course it was rude, and I couldn’t think of anything I could say that wouldn’t make things worse. But what struck me was that I had played both roles–teenage snot and dumpy lady–to perfection, and I’ve begun to suspect that maybe that’s the biggest joke in the universe: We become the people we despise.

As a teenager, I figured that fat people were like a communicable disease–stand too close to one and you might catch whatever loathsome germs they carried. I hated them for the lack of self-discipline, their poor personal habits, their obvious stupidity (if they were smart, would they go around looking fat in front of people like me?). At best, I was nice to fat people in the way that a nun is nice to a prisoner on his last day on death row. It was my charity.

OK, so maybe I’m exaggerating, but really–I was a massive jerk when it came to fat people. More to the point, I was terrified of becoming one. I ran at least a mile every day and dieted like California had swapped places with the Sudan. From the age of 15 until I was about 25 I can tell you exactly what I ate because it rarely varied: no breakfast, a hard-boiled egg or non-fat cup of yogurt for lunch with a salad of lettuce (no dressing), and for dinner a 4-ounce steak, broiled, with another dressing-less salad. 1 gallon of water each day. 1 stick of sugarless gum as a treat. That’s it.

Only exception happened after I married: My husband and I cooked a monthly feast–Japanese, Chinese, French–for my family as a Sunday dinner. I had a bodyfat level of 19% and was deeply depressed that I couldn’t get it down to my “ideal,” 12%. I would burst into tears if someone mentioned the word “fat.”

25 years later and a lot more than 19% bodyfat, I’ve learned a great deal. I’ve learned that new research is showing that a whole generation of women like me have permanent health problems, including obesity and its concomitant issues (diabetes, gallbladder diseases, orthopedic problems), because we convinced our bodies through overexercise and underfeeding that we lived in a permanent famine.

Our bodies responded by becoming very, very good at holding onto whatever tidbits of food they could get and when we gave up the famine in exhaustion–as you eventually must–all hell broke loose. We’ve done incalculable damage to ourselves…and we’ve become the thing we most despised: Fat.

We’re learning to worry more about being healthy than looking like supermodels–and that’s great. But I wish I’d learned that lesson 30 years ago–and I wish there was a way to convince the girls on that bench that it’s a lesson worth learning early.

Be careful what you don’t wish for, girls: You might get it anyway.